So what has this given me over Vista? At this stage, no huge UI differences apart from my new friend the Lighthouse down in the system tray
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Another cool feature is you can now connect to WiFi networks that don't broadcast their name, which you couldn't do with XP or Vista (AFAIK).
And lastly we've got the ability to mount Virtual HDs, which means I've been able to share drives between the Virtual PC and the actual box when I've needed to.
Apart from that a lot of the cool new features aren't available until the Beta, but you can use the Blue Badge unlocking feature to get at unfinsihed versions. A friend did it on a virtual machine, but the features weren't that stable so I gave it a miss.
I've also installed AVG Anti Virus and haven't had any problems with it, shame on you McAfee!